The movie briefly explains, Thalia’s sacrifice and Zeus taking pity on her and transforming her into a pine tree, creating a magical border around the camp so that no other half-blood would suffer from a fate as she did. In present day, Chiron and Mr. D investigate a Cyclops that has somehow passed through the border, and the cyclops is revealed to be Tyson, Percy’s half-brother. The camp is suddenly attacked by a Colchis Bull, who breaks through the border and ravages Camp Half-Blood. Percy finally defeats it with the help of Tyson, Annabeth, and Clarisse. Luke Castellan suddenly appears and confronts Percy, trying to convert him to his cause. When Percy refuses, Luke disappears.
The campers soon realize that Thalia’s tree has been poisoned and that they have been left vulnerable to attacks. Annabeth and Grover then find a way to save the tree as they learn about the Golden Fleece which has the power to heal almost anything and they then propose a quest to Mr. D, where they retrieve the Fleece from Polyphemus‘ Lair in CirceLand in the Sea of Monsters and use it to heal Thalia’s tree. Mr. D then announces the quest, but chooses Clarisse to lead the quest instead, much to Annabeth’s and Percy’s dismay.
Percy then convinces Grover and Annabeth to accompany him on the quest, and Tyson joins them against the groups’ wishes.[youtube:http://www.youtube.com/watch?v=w6aYjbpBm-E%5D
Firstly let me admit that I have read all the books in Percy Jackson & the Olympians series. So I could be a little biased against the movie. One of the scenes in the movie, looked like frame to frame rip from Harry Potter and the Chamber of Secrets (The taxi scene). The story of Percy Jackson & the Olympians: The Lightning Thief had deviated a lot from the book. Thor Freudenthal (Director) has made this movie closer to the book.
The special effects are good but it could have been much better especially since Percy and his friends were sailing through the sea of monster. Sadly quite a few monsters from the book are missing. In the sea of monster, we see only one monster: Charybdis which was a bit of let down.
There are lots of plot holes like Percy talking to the lake and expecting Poseidon to respond. Unfortunately for Percy, Poseidon is the “God of the Sea” and not lake! The conclusion of the movie is absolutely pathetic. The final fight sequence kind of shows that Titans are easy to deal with!
Personally I don’t know which movie is worse Percy Jackson: Sea of Monsters or Percy Jackson & the Olympians: The Lightning Thief. Watch it only if you are a fan of the series, even then you might be disappointed (like me)